@Karlos.
It's a movie! Over analysis ?
Room for a minor expectation adjustment?
Not even. It gets worse. I just couldn't be bothered to complete. However, in a nutshell:
Captain warns the team that a vicious storm is coming in, so the "scientists" take head back to the ship. Meanwhile, David (the droid) decides to take one of the urn like cylinders, unbeknown to his colleagues.
Meanwhile, lost dip**** geologist and biologist are trapped in the structure for the night and inevitably wind up back at the room with the urns / head and discover they are all oozing a black goo. One very reminiscent of the x-files. Then they find they aren't alone.
Biologist dude who was previously scared off by a dead body, is confronted by a metre long nasty alien worm thing that rears out of the black goo. Only now, rather than being freaked, he's all full of worm love. Approaching it with no sense of caution, it wraps around his arm and breaks it. An attempt to cut it off by the geologist fails and it grows a new head. The spray from cutting it turns out to be all alienesque melt-all acid and sprays over the geologist's helmet and it melts onto his face. He then falls face first into the goo.
There's one scene back aboard the ship that's interesting in which it is revealed that David is acting on someone's (revealed later) instructions and the possibility that the Weyland representitive supposedly in charge (played by Charlize Theron) may be an android because she is able to pin David to the wall and demand to know what "he" said, the response being to "try harder".
Later we see David disassembling the urn thing and isolating a drop of the black goo. He finds Dr Holloway, who despite making one of the greatest discoveries, if not the greatest discovery of all time and that his enormously far-fetched interpretation of the ancient depictions might be true, is having a sad and has proceeded to drink himself into a stupor. Simply, it seems, because they didn't find a live engineer to talk to. After just 6 hours of non-exploration....
David, one of the only characters with any depth, instantly recognises this brand of irreversible fail and decides the only sensible thing to do is spike his next drink with the black goo, because anybody that stupid deserves it. Probably. There's a brief exchange in which Dr Holloway tells David that humans made him because they could and David presumably finds that as disappointing as Dr Holloway travelling 36 light years to not speak to his maker. Or whatever, he deliberately exposes him to the black goo is the point.
Later, the other scientists have prepared the head for examination. Instead of some non-invasive cat scan or x-ray type work, they opt for the only thing to do when confronted with a priceless historical artefact that might be unique. They get David to break it open. Inside, is a remarkably well preserved humanoid head. Dead for 2000 years, but apparently still showing some signs of cellular activity.
In an amazing leap of intuition, Dr Shaw believes she can "trick it into thinking it's still alive" by pumping part of it's brain (that it might not anatomically even have, and they sure didn't perform any realistic scans on it to be sure) full of juice. By which I mean some 50 amps. Stand back, they are going to Science!
Anyway, it twitches a bit and subsequently explodes. Only after which do they take a sample for gene analysis. It turns out that they are genetically identical to humans! I mean despite being hulking albino, 9 foot tall and all-over bald.
Later, Dr Shaw is logging her results, pondering as to what caused the head to explode. I mean, it's not as if the gases released by electrolysis of all those fluids when you pump 50 amps through it might have caused it? A drunken Dr Shaw wanders in and she tells him the news that the engineers are basically human. He reacts by saying humans aren't special and anybody can create life. This triggers a cringingly delivered response that Dr Shaw is basically infertile and can't. As if to prove she just isn't trying hard enough, Dr Holloway proceeds to give her a good tumble. Can't make babies? Need moar sex!
Later he wakes up and notices something wrong with his eye when he looks in the mirror. In super close up, we recognise it as some sort of parasitic worm thing swimming around in his cornea, but he doesn't see it.
The next day, they go back to the structure to look for their colleagues, who for whatever reason, they aren't able to tell are dead already because their suits obviously don't have any physiological telemetry. That's just too silly.
Eventually they do find them. Once again, David wanders off mission and explores some other part of the ship and ultimately discovers some control room that resembles the one from the original alien move. He's able to activate more of the holographic recordings and witness some recoring of the crew preparing the ship for launch.
Dr Holloway becomes unwell and they make a return. By the time they get back, he's visibly looking quite ill and the boss won't let him back on board. Now, bearing in mind they had security guys with many quick and efficient weapons, they just torch him with a flamethrower. Obviously, it's not just David who thought he was a complete douchebag.
I don't recall at which point it happened now, but the geologist dude turns up again, all mutated and full of aggression and takes out a few crew, so that was a good call offing the guy, cuz that goo makes you go nasty.
Later, back on board the ship, the bereft Dr Shaw finds out she's pregnant. At which point we learn there's no medical crew on board (LOL, bit of an oversight!), so she's going to go into hypersleep. Right up until David tells her it's not a normal foetus and is already looking quite developed. She's now determined it has to go.
It turns out (luckily, was revealed earlier), that the boss woman had a "one of only a dozen made" medical pod that can perform all sorts of automated procedures. She gets there, only to discover it's only calibrated for male patients. So, she hastily programs it to perform an emergency C section on her.
If it doesn't sound ridiculous enough already, this machine cuts her open and takes out her womb sac. Which, even before she gets stapled up again, ruptures and reveals some horrible squid thing that had been growing in her. Now, if one drop of black goop in Holloway's drink was enough to turn his sperm into some sort of alien precursor, you might think that all that alienised amniotic fluid spilling into your wide open abdomen could be an issue, but apparently, it's a miraclue cure, for reason's we see later.
She escapes the pod, barely held together with stiches and struggles painfully through some presumably off-limits part of the ship and blunders into a room where Peter Weyland is being readied for his trip to the site. The same guy that was supposedly long dead on Earth! Yay, now we know who David was taking instructions from and why the medical pod might be calibrated for male patients. Nevertheless, there's no real reason it was all secret.